Please refer here for Cisco AP model comparisons.
I hope this helps.
Moderator for Cisco Customer Communities
As Kelli says prefer tot the compare series for exact details on each of the different AP models and their data sheets.
When I am recommending an Access Point for a customer (Be it Cisco or other vendors) the things that I first determine are:
I then look at the different data sheets for APs that will meet the needs of the customer, and conduct a predictive / hybrid site survey for the client (very important step) and if the coverage/ capacity is the same between different models that meet the requirements, then I give them a BOM with each model along with why I would choose one over the other.